Study On Image Reconstruction Algorithm Of Electrical Capacitance Tomography

Two-phase flow processes exit widely in industry field. Accurate measurement of multiphase flow can open out the mechanism of multiphase flow, set up model of multiphase flow, and also provide essential bases for forecast, design and optimized control of flow process. Process Tomography (PT) technology, which has been developed rapidly in recent ten years, has great developmental potential and wide industrial application prospect, Having many distinct advantages such as low cost, wide application field, simple structure, non-invasive measurement and better safety, Electrical Capacitance Tomography (ECT) has being the popular research direction and the main development in process tomography technique.The object of this dissertation is on the research of 12-electrode Electrical Capacitance Tomography system. The main topics studied are finite model and image reconstruction; the main works are as follows:1. An overall introduction of process tomography based on various sensing techniques was presented. Electrical Capacitance Tomography(ECT),including sensing technique and image reconstruction algorithms were especially reviewed.2. The study on Electrical Capacitance Tomography is carried out. The ECT sensor is analyzed through finite element method, the sensitivity fields is divided by triangle cell and the electrical capacitance values are deserved with different stimulate voltage. The sensitivity field is concluded and analyzed.3. A novel Landweber iteration is proposed based Tikhonov regularization. The iterate time is set 10 and it last about 0.1second.The simulation results show that the new algorithm is better than the Landweber 3.125%,1.389%,1.3892% on occupied spatial ratio(OSR) and 0.0069,0.0370,0.5209 on space image error(SIE). The results of experiment manifest that the convergence of new algorithm is improved than Landweber.